Efficacy of various irrigation methods for the removal of calcium hydroxide paste in the root canal

Abstract

In this study, we compared the efficacy of calcium hydroxide (Ca(OH)2) paste removal in the apical part of the root canal using various irrigation methods. Ninety extracted single-rooted teeth were prepared and split longitudinally. At the apical third, a standardized groove was made and Ca(OH)2 paste was inserted. The two split sections were reassembled and Ca(OH)2 paste was removed with 5 ml 2.5% NaOCl using three different irrigation protocols: conventional syringe irrigation (Control), sonic irrigation (Group 1), and ultrasonic irrigation (Group 2). Samples were split again and the remaining Ca(OH)2 paste was evaluated under a dental operating microscope using a 4-step scale: score 0, empty groove ; score 1, Ca(OH)2 paste present in less than half of the groove; score 2, Ca(OH)2 paste covers more than half of the groove; and score 3, Ca(OH)2 paste completely fills the groove. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney tests at 5% significance level. The groups irrigated with sonic (Group 1, 0.8 ± 0.81) and ultrasonic (Group 2, 1.0 ± 1.02) devices showed significantly better removal of Ca(OH)2 paste from the grooves, as compared to the group irrigated with conventional syringes (Control, 1.53 ± 0.82) (P < 0.05). However, there was no significant difference between the sonic and ultrasonic irrigation groups. The use of additional (sonic and ultrasonic) irrigation protocols enhanced Ca(OH)2 paste removal in the root canal as compared with conventional syringe irrigation.